“Whenever you have a zoom lens with a large range,” award-winning travel photographer and Sony Artisan of Imaging Bob Krist observes, “you almost always have to put up with some funky focus quirks—a lot of hunting and pecking, especially at the longer end of the zoom range.” Just a split second of delay might be the difference between nailing the shot and missing the peak action or a precise arrangement of moving elements in your frame. “With the RX10 IV, even with its enormous zoom range, the focusing is fast, responsive and sure-footed,” says Krist, who has shot with the camera extensively in destinations around the globe. “It makes it easier to whip from, say, a wide-angle scene to a more intimate composition you may spot in that wider view.”

The Sony RX10 IV’s advanced autofocus system is one of the key differentiators that sets this camera apart from other long-zoom, all-in-one cameras. The RX10 IV’s autofocus system employs 315 phase-detection AF points that cover approximately 65 percent of the 1.0-inch Exmor RS CMOS imaging sensor and enable the camera to acquire focus in as little as 0.03 seconds. High-density Tracking AF Technology allows the RX10 IV to track moving subjects for continuous sharp focus as it captures up to 24 frames per second for up to 249 frames in a single burst—exceptionally fast and especially useful for a variety of subjects from sports and wildlife photography to candid portraits and street scenes. “It’s no use having a super zoom range if the camera’s autofocus is not fast enough to keep up with your subjects,” says Krist.

“When you think of fast focus on a camera with a huge zoom range,” he continues, “you naturally think of sports or wildlife scenarios at the long end of the zoom. But there are other situations where it comes in just as handy. As I walked from the bright sunlight into a dark little tavern in Mineral de Pozos in Mexico’s central high desert, I saw the cowboy and the cat starting out the door from his perch under the barstool. I swung the camera around, held it vertically and shot from the hip (in Rich B&W mode) to catch the action before the cat left the frame.

“Not only did the camera focus precisely, it did so quickly and silently,” Krist reports, “and it made the appropriate exposure adjustments as well. I often use Silent Shutter to be less obtrusive, and, in this case, the young ‘charro’ didn’t even know I took the picture. I did stay on and introduce myself, bought a beer and made more portraits, but that sterling moment with the cat was something I could not recreate. For me, this kind of versatility makes the RX10 IV the perfect travel camera.”

In addition to still photography, the RX10 IV also excels at video. It’s capable of recording ultra-high resolution 4K video with the same Fast Hybrid AF used for still images and offers both headphone and microphone accessory jacks for superior sound quality and usability. “In many ways,” Krist confides, “for both my still and video shooting, the Sony RX10 IV is my secret weapon. To have a zoom lens with a 600mm reach that is this sharp and this responsive in such a compact package is an incredible advantage. It simply allows you to grab shots that you could never get before.

“I’m certain that if more pros weren’t locked in their old-fashioned concepts about the image quality a compact zoom camera can deliver, it would be their secret weapon, too. But that’s OK, because the longer it stays my secret, the more of a drop I have on my competition—a freelancer’s altruism can only go so far.”